雙顎正顎手術治療女性骨性三級咬合病患之側顏輪廓標示點變化之探討

Investigation into Changed of Soft Tissue Landmarks and Construcred Intermediate Points on Facial Proplie in Skeletal Class III Female Patients Treated by Bimaxillary Surgery

目的：女性病患對於以正顎手術來改善骨性異常咬合時，通常較重視顏面外觀的變化，本篇實驗的目的為研究骨性三級異常咬合之女性病患側顏輪廓標示點於雙顎正顎手術後的變化。方法：本篇研究揀選了16位骨性三級異常咬合的女性成年病患，所有的病人都接受矯正合併上下顎正顎手術治療，且術式皆是上顎勒福一型截骨術（Le Fort I osteotomy）合併下顎雙側枝矢向分裂骨切開術（bilateral sagittal split osteotomy）；在術前及術後測顱分析及測顱軟硬組織標示點標明後，用以分析軟硬組織於手術後的移動比率及其相關程度。結果：所有的病患在手術後都有和諧的上下顎骨關係及顯著的外型變化。不管在水平還是垂直方向，所有下顎的軟硬組織標示點間均表現出高度的相關性，且在水平方向的移動比率接近於1:1；於垂直方向的移動比率則接近0.9:1。在上顎方面，大多的軟硬組織相關性落於中等程度，僅有i-LS與U1E之間有著高度的相關性，且於水平方向移動比率接近0.8:1，而垂直方向則為0.6:1。然而鼻尖（nasal tip）及鼻底（nasal base）區域的軟硬組織移動相關性則不明顯。結論：本研究顯示上下顎軟硬組織標示點間有著中等至高等程度的相關性，表示在側顏輪廓上下顎軟硬組織間的移動比率是可以信賴的。此外，本研究所建構的中間標示點（intermediate points）與鄰近的主要標示點有著相似的軟硬組織移動比率及高度關聯性。此結果讓臨床醫師在評估分析時，有更多的標示點可用來預測及建構更完整的側顏輪廓。

Objective: Improving facial profile by orthognathic surgery is requested more often by female patients. The aim of this study is to investigate the responses of major labeled landmarks and constructed intermediate points on facial profiles of Class III female patients treated by bimaxillary surgery. Material and methods: 16 skeletal Class III female patients requiring Le Fort I osteotomy and bilateral sagittal split osteotomy were selected in this study. Cephalometric tracing was carried out, and selected landmarks were digitized. The surgical outcome and the correlation of soft to hard tissue changes were assessed. Results: The surgical result revealed normalized skeletal relationship and acceptable facial profile for all subjects. In horizontal and vertical direction, mandibular movement ratio of soft to hard tissue showed approaching 1:1 and 0.9:1 with strong correlation. The maxillary components presented moderate correlation except i-LS to U1E with movement ratio around 0.8:1 horizontally and 0.6:1 vertically. The paired groups in the nasal region presented weak correlation. Conclusion: The maxillary and mandibular movement ratios showed acceptable reliability in facial profile change. Furthermore, the constructed intermediate points also possessed the ratios of movement and the correlation coefficients similar to the adjacent landmarks. These results can provide clinicians with further more reliable landmarks to configure the planning profile.